Posted
by
Hemos
on Tuesday April 13, 1999 @09:10PM
from the cheap-clean-limitless dept.

ABCNews is featuring some interesting coverage about the different fusion research going on around the country. The article itself talks about the shutdown of the Tokamak, and the differences between it and some of the new developments. One of the best points is talking about the pittance of money that is being put into the research, versus the known benefits of making advances in this.

If fusion were cold, why would we want it? In all or vast technologies we only can harness heat. Even fission is used for the purpose of boiling water. So if by "cold" fusion we mean giving off less heat, then it's useless. I've always been confused by the term cold fusion, could someone please fill me in as to what it is?

Note that you can also power said plants by mirrors heating water-filled pipes or focussing onto a much smaller set of solar panels; I believe there's a test plant somewhere that already does the former. (This really just reduces your manufacturing and wiring costs, raw silicon is cheap and plentiful (sand)) With the right mirror, you might even reflect only the wavelengths of light that plants don't use (they are green, which means they reflect green light), and thus still have vegetation growing in your solar collection field. You could also mix in wind power-based systems using the same land with only a marginal impact on efficiency.

Combine this with fuel cells and geothermal heat pumps, and we could really reduce our use of fossil fuels. But with oil costs so low now, the incentive is small.

Is there any corporation or research unit that wants funding? Perhaps a Slashdot collective, and if each user of all 200,000 of us sends 10 dollars, we could get some sort of share or ownership of the technologies involved =)

Hmm.. and if each of us sends 200 dollars we could build our own reactor and maintain it for a little while.

ANother drawback to Solar - the environmental impact of manufacturing those solar cells. Strong acids and detergents are used in the process, and pollute the fsck out of the environment, as bad as semiconductor manufacturing.

Not to mention the overall economization that goes on in the electrical process (because they produce so little current for such a high cost), you end up with lots of batteries, basically, so there's another huge, huge environmental hazard, disposing of all those lead-acid batteries.

was the college girls that would work there during the summer! I was like 21 at the time (1981) and we (the techs) would take half a vacation day on Fridays during the summer, get cases of wine, a keg, setup volleyball nets and have a blast out by the runway. (They have a small airport, dontcha know.) That was when the TFTR was still under construction and not too long after the gas crisis, so it seemed like there was a future in it. Nice to be working on something that was good for the planet, had great tech toys AND babes!

They used to have a sailplane club, and could fly hotshot physicists right in. Jimmie Carter landed there when he visited. It was also a great place to take a run on a cycle.

So I guess the gun club for skeet shooting is probably history too, eh?:-) It was an old wooden building, small but with a big room and long long table. We used to have chili cook-offs and such there. Sigh.

"Remember that ALL forms of energy have roots in solar fusion. There are no exceptions to this!"

Sorry, Big Blue, but you'll find that fission has nothing to do with the sun...fissile materials come from whatever star that blew up and formed the heavier elements from which the earth (and the rest of the solar system) condensed.

Also, if zero-point field energy proves genuine, the sun has nothing to do with that, either. In fact, we can probably rule out fusion from your set of things powered by the sun.

"Can you say cars? Hybrid power plants can double the efficiency for peanuts"

I was hoping you'd go down that street. Tell me, once you've gotten your "super-efficient" hybrid car in your driveway, how are you going to charge it? What's that you say, you'll plug it in? Super! But just where do you think that electricity is coming from, God's butt? It's coming from your utility, good sir, and there's a real good probability that that electricity is being produced by burning coal or gas. And then it gets shunted through mile after mile of wire and transformers and finally trickles out that power spigot in your garage. Is that an efficient use of that fuel?

You plug that expensive, plastic and aluminum deathtrap into your outlet, and you'll be paying not only to put gas in the fuel tank, but electric bills that are several times higher.

And if the idea catches on, then whole neighborhoods will start drawing more power, putting greater demand on the utility company to provide more electricity...in a time when many communities already experience summertime brownouts thanks to excessive peak loads!

The only time automobiles like this truly become practical is when the utility has a source of power like nuclear (fission presently, or fusion someday). THEN electric and hybrid cars start to make more sense. Otherwise you're shifting the pollution away from the individual car and onto the power company...which has to burn more fuel to get the same amount of power to you.

Ummm, pardon me, but don't we already do this? Most office and industrial construction is done with an eye towards reducing energy demands for one very obvious reason: it saves the client money. So there's a real strong incentive there already without even considering feel-good tax incentives.

The problem isn't really one of conservation, we're doing that almost to practical limits. It's one of an expanding economy, and an expanding economy with all its new office buildings and industrial plants requires more power. That power has to come from somewhere.

A further point you've missed is that power plants that have been built to date aren't going to last forever. I know it's a damn shame, but those coal-fired plants are going to have to be replaced eventually. No new nuclear plants are even planned at the moment (and they're gonna get old and shut down too), so what's the option? A bigger coal plant? Natural gas? But...don't most geologists acknowledge that these so-called fossil fuels are in limited, non-renewable supply? They're gonna get pretty pricey before they run out, you know.

Nope, your rant against "Star Trek" mentalities aside, we need something better. Fusion looks good, zero-point field energy might have a future, and even improvements in fission reactors might see use if people could over-come their hysterical anti-nuke knee-jerks.

Oh, but so much more too. I did an internship at PPPL last summer (where the NSTX is located) and took some classes. One of the classes was on the heating systems, and the professor noted that the microwave power was equivalent to some 10k household microwaves, or enough to "nuke a Holstein cow in about 10 seconds." I think this was referring to the TFTR; I am pretty sure they've increased the heating capacity for the NSTX.

ISTR that fusion will not make an end to nuclear waste. The reactor itself will be highly contaminated, so after the end of it's service life, there will still be a slight problem of finding a safe place for several hundreds (thousands?) tons of radioactive material.

Still, it's a good thing to get away with waste from the running production.

I was a graduate student at the University of Texas at Austin in the late 70's. One day I had my Physics class taken on a tour of the tokamak facility, the same tour given to civic leaders, congressmen, etc. We were told that a commercial fusion reactor would be functioning by the year 2000. Absolutely. No doubt.

I was also surprised to learn (as another person noted above) just how much nuclear waste a fusion reactor can generate. It made me and, I hope, my students a bit skeptical of the fission => bad, fusion => good mythology. Note how the ABC article suggests that fission causes air pollution and global warming: "...the fusion process can't cause a "meltdown" reaction and doesn't contribute to air pollution, acid rain or the greenhouse effect."

Sorry, but the only black holes I've been able to find are in my dryer - I still don't know where the Other Sock goes. All the other black holes we know of are about a million lightyears away. Not terribly efficient. Maybe we can invite one over for lunch?

The fissionable material is a by-product of solar fusion. Uranium was once hydrogen in an ancient star. The formation of heavier elements was part of its death. Without hydrogen fusion to work against the force of gravity, the star slowly collapsed. That collapse increased the pressure and temperature, which in turn caused the production of heavier elements. The end result was a nova, which expelled that material from which formed the world we live on today.

I realize that the connection between fission and fusion is distant; but the origin of all elements beyond hydrogen resides in the last part of a stars life cycle. That connection is no more or less trivial than the connection between oil and photosynthesis.

For all the conservation and all the wonderful attempts at "alternative" energy sources, the bottom line we are completely dependent on fossil fuels. There is no aspect of our civilization that is not somehow connected to cheap sources of stored energy. The US was electrified in the 20s' and, along with the rest of the world, we've been consuming that stored energy at startling rates. Next time you have the chance to view a major city at night from above, think about the thousands of similar cities around the world - each with millions of individuals - all consuming that stored energy, all the time. With that realized, I cannot accept the proposition that our baseline power needs are going to be satisfied by the wind, solar, and geo power sources that, while triumphs of invention and ingenuity, are too few and far in-between for the bulk of our needs. Remember that ALL forms of energy have roots in solar fusion. There are no exceptions to this! Like the earth is a resistor in a circuit where the sun is the battery and interstellar space is the ground. If we are going to continue to survive en-mass beyond the point when the stored energy boom ends, there is no better option that putting a piece of the sun in a bottle. (Keep your eyes on bio-gassification too)

A minor misunderstanding has occurred, possibly due to my choice of words.

My position is that all forms of energy can be traced back to the natural process of solar fusion. Whether that process occurs in our sun or some other star isn't important to understanding that process, or to how we have learned to use the byproducts of that process.

RE: Fusion is unnecessary. This is also true, but unfortunately it will remain true only so long as we can harvest a cheap supply of energy from the reserves of the earth.

A strict discipline of conservation will help us now - to stretch out what we have - and later - to better utilize a new source of baseline power. It's just a matter of time before we are forced to adopt that new energy source.

IMHO, the only thing preventing us from realizing hot fusion now is our nature as a species. We currently have a source of energy for all our needs that has been with us for as long as any living person can remember - oil. We use if for producing everything that makes modern life possible. Until that source of power shows tangible signs of vanishing the incentive to conserve and ultimately replace it just isn't there. For the educated, we know very well that the oil, coal, and gas are running out. We can say that it will be gone within a generation. But until the broad masses of people, who don't bother to consider the realities of that wake up to the peril, we'll keep sailing along on our free energy ride. This is exacerbated by the greed and FUD that permeates business and government, who's only desire is for short-term profit. History is replete with examples of civilizations that have gone down this road to self-destruction; used up an easy to exploit natural resource, breeding like rabbits until the basis was exhausted and the system collapsed. Even current history can illustrate this lack of awareness.

As for "all that crap", I am inclined to agree with you there too. The existing alternatives to fossil fuel leave much to be desired. But burning anything isn't the answer. Nature has provided the best (and only) source of long term power - fusion. In order to survive and persist, we absolutely must master this natural process.

Please, consider for a moment what would happen today if we lost our remaining fossil fuels. We need them to produce food (those high-yield crops require chemically fertilized soil to be productive). The machinery for food production requires energy. All of our electrical, heating, transportation, manufacturing, and medical science require the petroleum energy subsidy to work. Denied this and many millions would die slow painful deaths of starvation and exposure, as every major city collapsed socially.

The bottom line is we need to make fusion work, because conservation isn't enough. When the fossil fuel is gone, no amount of frugality can make 0 amps do anything.

I may be wrong on this one, in truth, I hope that I am. But if ZPE is the EMR that you find in empty space then that energy is in an unusable state. The reasons are in the nature of energy movement needed to produce work. In order to convert energy into work, it must move from a higher concentration to a lower concentration (the so-called sink). The problem would seem to be that ZPE represents the "final" sink. We cannot extract the ZPE because there is no "lower" sink for it to flow into. (Refer to Carnot's description of a heat engine for more on this.) The vast pool of ZPE can be compared to another huge reservoir of energy that is stored in the world's oceans. If we could extract that energy, we would have our alternative source. Unfortunately it would take more outside energy to extract usable amounts of power from the ocean; we most likely will find ZPE to be unusable for the same reason.

[Regarding the ocean as a source of power, I remember reading about a proposed heat exchange based system that would move heat from the warm surface down into the colder depths - generating electricity along the way. The analysis concluded that while such an approach could technically produces usable power, the economies of building/maintaining the installation would far exceed the value of energy produced. There was also the unknown environmental impact of the heat introduced to the depths.]

Enough of this cold fusion crap. There are very good physical reasons why cold fusion is IMPOSSIBLE. In order to fuse, you have to get nuclei close enough together so that they feel the strong force. The energy involved in getting them together is so high (~5 million K) that it CANNOT BE DONE AT ROOM TEMPERATURE! Sheesh.

High-temperature fusion has basically turned into a game of controlling turbulence. Nobody can contain the plasmas. As a physicist, I think the cutting of funding in the field is a good idea until the turbulence is better understood. There was a plan to build ITER (International Thermonuclear Experimental Reactor). The thing was huge -- like 4 stories, and would have cost several billion. Needless to say it was cancelled. It might have contained the plasmas by brute force, but at ~billions per reactor, this is hardly an improvement over fission.

Sorry guys, you don't see the point. Nobody is funding it because they already have a weapon from the technology. The only projects that get funded are weapon systems or weapons support systems with very few exceptions. That's a major reason my my major was physics but my career is CS.

Yep, I do know. Like I said, my training is nuclear physics but my career is CS. That was a choice based on morals.

A fission trigger will still pollute enough but the yield will be enhanced by fusion. They're both nukes as designed by the current arsenals.

As for my funding comment, the comment was in response to a US based observation. Since you called me on it, you obviously realized it was US based as well. I can only speak of the job market I'm in. I guess I didn't realize readers needed such specific context.

Hot fusion is a hard problem, and will probably stay that way for many years to come. It will change the world when it's economically feasible, but it will always be a big, expensive thing to build and maintain (keeping the sun in a jar is not cheap). Forget about the developing world sharing in the hot fusion boom (unless someone there gets a hold of a fusion bomb and threatens the energy rich nations of the world with a different kind of boom).

Cold fusion would be fantastic, because you could do that in your basement, filtering the heavy hydrogen out of your tap water. This would be an even bigger win, because the whole world could afford it. Of course, cold fusion seems even less likely than hot right now.

Short run we should focus on moving to cleaner burning fossil fuels like natural gas, and slightly longer run we should think about converting to a fuel-cell based hydrogen economy. There are big efficiency and environmental wins to be had, without trying to contain a solar furnace in a magnetic bottle.

Unfortunately, there does not seem to be a place for the reduction of demand in our modern economics. The growth of our economy seems hinged on getting more soccer moms to buy more chevy suburbans (4wd model, natch) and more raymond weil watches.

Nerds are part of the problem. They have voracious appetites for toys.

The question of wether fusion reactors would produce significant radioactive byproducts is a little bit tricky. Unlike Fision, where you will inevitably get hoards of neutrons from the reaction and make everything near it glow in the dark, fusion depends on what fuels you use.

A lot of the research done is with D->T reactions, which make Helium-4 (which makes you talk funny) and a neutron, (which makes you glow) However, this is not the only fusion fuel source under consideration.

The reason fusion nukes release as much radiation as fission nukes is because they rely on fission to release the heat necessary to jump-start the fussion process. And then there are neutron bombs...

Fusion produces quite a bit of radiation too. Certainly gamma radiation, but quite a bit of neutron radiation also, and this is what presents the most danger (as it is this that makes surrounding materials radioactive).

Conventional fusion weapons fuse lithium and deuterium, IIRC. Li7 + H2 -> He4 + He4 + n, or He3 + He4 + 2n, or He3 + He3 + 3n, or any of a number of other decay chains. If I understand correctly, He3 is actually more likely to form, because energetic He4 nuclei can shed their excess energy easily by emitting neutrons and turning into He3. So in summary, the neutron flux from fusion is nothing to sneeze at, and is actually greater per unit mass than that from fission.

Neutron bombs are a special case. They can be built by modifying either fission or fusion bombs, though.

Short run we should focus on moving to cleaner burning fossil fuels like natural gas, and slightly longer run we should think about converting to a fuel-cell based hydrogen economy. There are big efficiency and environmental wins to be had, without trying to contain a solar furnace in a magnetic bottle.

Why not use methanol? It's easy to transport, can be stored at high density, burns cleanly, and can be produced reasonably efficiently using solar energy (i.e. grow plants and ferment them). If you're trying to produce mechanical energy, then you can do that directly instead of converting from electrical energy produced by fuel cells. If you're trying to produce electricity, IIRC there were fuel cells that could process methanol. Or you could run a generator off of a methanol engine.

This reminds me - does anyone have a URL to an article that discusses in detail the many magnetic confinement schemes that have been tried over the years? In particular, I'm wondering how a "spheromak" works (the configuration described in this article is _not_ a "spheromak"), though I could stand to brush up on stellarators, also.

I was dissappointed that the article doesn't mention that there is also promising research into other methods of fusion; namely at least one method that doesn't require extremely high temperatures that neccessitate the huge, inefficient reactor in the first place. I can't recall where the research is being done, but there's at least one non-thermo approach that uses electrons concentrated in the center of a spherical chamber (they are continuously fired into the center in a way that's kind of the opposite of what happens inside a television); the electrons create a huge potential well and attract the (ionic) fuel, which then doesn't actually collide with the electrons but rather with other fuel particles also pulled into the center... at very high speeds. Doesn't require high temperatures to attain the neccessary particle speeds... those suckers have to ram into one another *hard*, but heating them up isn't the only way to do that. The original research was done in the sixties, I believe, but it never became efficient because there was no way to keep the concentration of electrons in the center without losing most of them. Thermonuclear (brute-force) methods took over in the seventies... but recently I hear research into this alternate method is starting up again, and looks quite promising! So, anybody have a link for this research?

This is *not* cold fusion, by any of the several definitions; this is *thermo*nuclear fusion. That is, getting atoms (well, nuclei) to collide by heating them up a lot. The whole 'cold fusion' fiasco ala Pons and Fleishman (sp?) has cooled down a lot (no pun intended), but it still isn't mainstream science. In fact, the continuing research into the effect they described is no longer even classified generally as fusion, and most don't see any possibility of large-scale energy production using that effect. However, there still *is* the possibility of real non-thermonuclear (ie, 'cold') fusion... see my other post.

It's not hot, but it's not "fusion" either, at least not as I understand it. There continues to be disagreement -- deep disagreement -- about what actually occurs in so-called cold-fusion reactions, but while I'm convinced there is something there, I'm far from convinced that it's anything other than a poorly understood chemical reaction.

"Cold fusion" research is mainly conducted in physics labs off the beaten path -- the mainstream boys won't touch it. Until somebody can fully explain it and create consistently duplicatable experiments, it'll remain an oddity.

As I mentioned in another thread, yes, matter/antimatter is a full 100% on the E=mc^2 conversion, while Fusion is only about 10%. But the fuel for fusion is deuterium, which we got a whole lot of sitting in the ocean. Annihilation, on the other hand, requires antimatter, which is another story. Currently, an international group of physicists is using the largest single magnet ever made to see if there are in fact galaxies of antimatter out there. I was at a lecture by Sheldon Glashow (part of the pair that unified Weak and Electromagnetic forces) in which he claimed to have (with a colleague) proved that there aren't any galaxies of antimatter within a light-age-of-the-universe of us, or something like that. So all we're left with is the matter/antimatter pairs that spontaneously appear. An interesting application of that stuff is Hawking radiation. This is how you get energy out of a black hole. Let me try a really bad explanation: A matter/antimatter pair spontaneously forms at the event horizon of a black hole, creating an energy debt. The antimatter part gets sucked into the black hole and annihilates with part of the black hole, making it spin slower and have less mass and fulfilling the energy debt. Then we have a new antimatter particle that we can collide with our own non-black-hole-in matter particle, getting the energy from the black hole. Cool, huh? Yes, just like annihilation in general: really cool, but not likely to be of practical application for at least a century. Fusion, on the other hand . . .

Nuclei are composed of protons and (except in normal hydrogen) neutrons. That makes them positively charged. Positive charges repel each other. As the original poster said, you have to give the nuclei extremely large amounts of energy to get the nuclei close enough for the strong nuclear force to dominate.

A quick estimate... nuclei are of the order 10^-15 m in size. The potential barrier between two protons at this separation is about 230 J. This energy is comparable to that of a a 16lb (7.3 kg) bowling ball moving at 26.3 ft/s (8 m/s). That's a lot of damn energy for two sub-atomic particles to have. The temperature required for this to take place is on the order of millions of Kelvin. I hardly call that COLD fusion.

I don't care how much damn funding you give them, you can't push two protons together at room temperature (300K or so).

And your analogy about the Earth being the center of the Universe isn't even relevant. That came from the idea that God made man in His image, and thus, we must be the favored of all His creations. Then, there were incomplete observations to "support" this theory.

Cold fusion is doomed by the fundamental laws of physics, which we have a much better grasp of that we did hundreds of years ago.

That's 1.3 kW *per square meter*, or in other words, that is the flux. Given 100% efficiency, a 1 m^2 solar panel would be able to power 13 100W light bulbs. Of course, we can talk about major appliances... ISTR my microwave oven requires about 6-700 W, that's a.5 m^2 panel.

Of course, there is the problem with overcast days... what do you do when you have a cold front stalled in your area, and are without any direct sunlight for a week? Your reserves are sorely taxed, if not completely depleted.

There are efficiency, storage, and distribution issues to consider, also. What about "power plants"? Would they install solar panels on your roof, then charge you for the energy they store? Or would it be a privately owned panel? In that case, what are you to do when yours goes offline? Expect some good natured neighbor to let you tap into his reserves?

I just don't see how solar power is feasible as a major source of energy.

I recently read an article on the comparitive efficiency, regarding cost/output of various power sources. Fission scored higher than solar. (actually fission scores higher than everything, right now). This makes your suggestion a little confusing. Why should the US government spend millions on switching to a less efficient power source than their current one, only to have it superseded by fusion, which would probably be even more efficient than fission, and certainly much cleaner.

Furthermore, 6000 square miles is an immense space. It's actually about 2/3 of Maryland.

There's a theory that black holes are all around us and they contain antimatter. We just need to find these scarce black holes. There's another theory that they may be related to universal microwave radiation.

If you can generate plasma (helium nuclei, and that's not that hard), you can generate antimatter. There's a nuclear reaction with a common element that, when exposed to alpha particles (the plasma) generates positrons. But then things get sticky...

First, the process also generates free neutrons, which are a pain in the butt to control.

Second, if a fuel pellet of the element were to be used, it is most likely that the positrons would react with the rest of the fuel pellet instead of becoming free to be electromagnetically regulated. That would result in chaos, an uncontrolled reaction.

Third, even if the other shortcomings were worked around, and this is the part that has perplexed me: What do you do with the free energy from the matter/antimatter fusion? A positron/electron pair fusion will basically generate a large gamma photon burst, as well as some free neutrinos and (I think) harmless other bits. But, gamma photons have such a high frequency and short wavelength that there's no good way to harness them.

If anybody's willing to solve those other bits, I'll go dig out one of my notebooks that has the formula for the reaction and things.;}

Solar collectors are terribly inefficient and require a LOT of space even working at 100% efficiency. When you make something that big, then you have problems with keeping it together and maintenance on top of that. If you keep it on earth they you have the problem with cleaning them, finding room for them (imagine trying to power a city with solar collectors, you'd need an area the size of a city with solar collectors to power a city. Combined with the fact that that many solar collectors would cost a ton in materials (cost of assembly would be small due to mass production).

Next suggestion, put it in space. Sure, but they you have the problem with maintenace up there, microasteroids, and transmission problems.

Fusion has one big advantage over solar power. Its small and portable. Try using solar power under the sea. Impossible. Put a fusion reactor on the deck of the titanic with some tritium collectors and you have a self sustaining energy supply.

Think about what your suggesting for the moment. An area the size of 1/1000 the area of the united states. That may not seem like a lot, but it is.

First, I don't doubt your facts, actually I think that they are very conservative estimates but I'm argueing from a logistics point of view.

There are only two ways that I can see inwhich that large an area of solar panels can be setup, either on top of existing infrastructure (roofs, etc), or on open area.

On top of existing infrastructure would prove impossible to maintain. Think about how long it takes roofers to get onto a roof or cable remair men to get to cables. So that is out of the question.

The second is open areas. 1/1000 the size of the united states. From an ecological standpoint it would be a disaster. If you wanted to sacrifice that much area then you could do it for a lot less with hydroelectic dams (falling water is also free).

Even if you didn't worry about surface area, then you would have to look at material costs. Solar panels are made up of silicon. I personally can't even imagine producing 1000 mi^2 of solar panels. Roads are made in a bulk process and don't even come close to covering 1000 mi^2 in the us. Add into that quality control and you would have a process that makes fusion power look like peanuts. Its just not a feasible alternative.

ITER is really one of the last big projects left from the 80s that is still running. It was designed with the philosophy if we get a small reaction with a small reactor, we'll get a big reaction with a big reactor. And, as a result, they hope to get the efficiencies required for ignition. I totally agree though that it is the wrong philosophy. However, as you noted, the only country that seems to be the notable exception is japan, who is one of the major contributors to ITER.

For those of you who havn't heard of ITER, its really a massive reactor. In present day reactors it isn't common for to have to crouch when doing maintenance inside, however the ITER reactor is 3 stories tall inside! Its really an amazing feat when you consider the stresses that the walls of the tokamak are subjected to.

I've seen wind power attempted. Actually, being from Hawaii, I've seen a LOT of harebrained schemes. Like the one where you pump cold water from the bottom of the ocean and let it pour over turbines, or the wave power things or any number of weird projects. The fact is, there is plenty of energy if you know how to harness it. But as long as we keep buying fossil fuels, there is no incentive to research new power.

Ummm, I'm not sure I would invest any money in anything that claims to be cold fusion. I won't say that it isn't possible, becuase thats always a stupid thing to say, but I don't think any physicists are trying to get "cold fusion" to work. This is merely an improvement in the design of old fusion technology. It still uses more energy to fire this thing up then it produces, so don't get to excited yet. But all improvement are a good thing.

Do you know how much damn a fusion bomb could do, a lot more than a nuke. And it would have low radiation meaning that the guy dropping could wait a few years and move on in.

Um, fusion bombs have been around for a long time. There are two types of nukes: atomic (uses fission) and thermonuclear (fusion). The reason fusion nukes release as much radiation as fission nukes is because they rely on fission to release the heat necessary to jump-start the fussion process. And then there are neutron bombs...

Besides, sapping power from the Sun is terribly short sighted - what do you do when the sun goes out? That's just the kind of thinking that led to the Y2K problem!

No, the only real solution is for us to gather a portion of the population together to live in pods where we harvest thier bio-electric energy. I suggest we start with a certain campus in Redmond - we'd all be much safer if they were all in pods, living out thier lives developing and releasing W2K in an imaginary universe.

The average house today uses 100amp service (220 volts), and most NEW houses need a 200 amp (220 volt) service.

True, though I doubt houses use 100 amps 24 hours a day!

Most current and new houses, and appliances (yes, PCs are guzzlers, but Netwinders and Laptops aren't) are based on the assumption of cheap power. Off-grid solar houses of today use MUCH less power, which is obvious when you consider the solar panel cost of driving the typical energy-inefficient house of today.

Some solar installations are designed to supply high peak power through more batteries -- it's not unusual for a solar home to be able to power all typical shop tools, but maybe not all at once. Ideally one can use "the (solar) grid" to supply the high peak power demands.

My understanding is that we are burning fossil fuels at a much higher rate (orders of magnitude) than they are being produced (which takes geologic time). At some point in the future, fossil fuels will become scarce. The only question is when. Unfortunately, no one has a good answer here.

Even if scarcity of fossil fuels doesn't happen until Y3K, the pollution caused by fossil fuels and political uncertainties (remember the OPEC embargo) imply that we should search for cleaner and more reliable alternatives. Fusion research (the hot kind) is exactly the kind of thing the government should sponsor. The end goal is too long-term and risky for corporations, but it has great potential if it can be made to work. The supply of deuterium and tritium [how come this word is not in my/usr/dict/words] is finite, but much, much larger than fossil fuels.

I think other alternatives should be investigated, too. It would be foolish not to.

Fusion seems to be the much more sensical version of creating power, at least vs. fission. Let's see here "the radioactivity produced by a fusion reactor is 100,000 times less than in an equivalent fission reactor. " That sounds like a plus. Not to mention "Construction of NSTX was completed on budget and months ahead of schedule, Richardson noted." That happens a lot for gov. funded ops. And the best/funniest "That proved the reactor could create a plasma with its giant magnets and just one of its heating systems, which uses an electrical current, like a toaster or space heater." One helluva toaster, eh. And how 'bout the big 'space heater' in the sky (a.k.a. the Sun)? This guy should go on the road. Anyway, clean energy you get from water, that doesn't go boom? Sounds worthwhile. Let's get Big Bill Gates to drop a billion or so on it. It fits with his ultimate plan (i.e. become GOD). Microsoft Sun v1.6.6.5 (oh wait, copyright infringement, or a crazy merger{The Network is the computer, no, no, Windows is the computer,grrr,grrr})

I am a graduate student, doing my thesis research at PPPL. If anyone is in the immediate area and is interested in seeing the tokamaks (and other plasma experiments) feel free to e-mail me and we can try to set up a tour....

I work on a much smaller experiment -- I came in to Princeton wanting to work on fusion, but I got really turned off by the politics involved...

> Tritium doesn't exist in nature. So how do we get it? > From Fission reactors of course. So the fact of the >..... > MYTH I: Fusion Fuel is cheap and abundant, not so.

Fission reactors are not the only source of tritium! Yes, they provide neutrons, yes they are used now by the gubment to produce tritium for nuclear weapons. But you don't have to use neutrons from a fission reactor!!! Where, you ask do you get these neutrons -- from the FUSION reactor itself. Yep, like a fast breeder fission reactor, fusion plants will make tritium by employing a blanket containing lithium. This will produce plenty of tritium for the reactor to operate. I give you that to start the process up, you will have to have an alternative source of tritium, and a fission reactor may be the choice for that (BTW -- the half life of tritium is about 12 years).

> Now the problem of radiation. Fusion produces huge quantities of > Neutrons, even more than Fission produces. This means > that the materials in and around the reactor will be > constantly bombarded and they will be converted into > radioactive isotopes by the neutrons. This is ignoring > the problem of secondary radiation created by the > countless fission reactors required to produce the > tritium needed to run the fusion reactors. So fusion > isn't so clean. >... >MYTH II: Fusion power is clean. Busted!!!

Again, you don't quite have your facts straight... Fusion does produce neutrons, but nowhere near the amount present inside a fission reactor!! A fusion reactor will have a neutron power load on its walls that is about the same as the neutron power flux in a fission reactor, but the spectrum of neutrons is much different. The fusion neutrons (from D-T) are 14 MeV -- whereas the fission neutron spectrum is a thermal one, with the average energy about 0.0025 eV (well, a little bigger than room temperature, but many many orders of magnitude less than the fusion neutrons). Power flux is essentially energy times density. So the density of fusion neutrons is much much lower than that in a fission reactor (for the same power load on the walls).

The radiation problem in fusion reactors is fundamentally different than in fission plants. Yes, these fusion neutrons are absorbed by materials and thereby make them radioactive. But we have a CHOICE in what materials we put next to a fusion reactor (we have no choice but to use uranium or plutonium in a fission plant). So we can minimize the activation caused by these neutrons. Even using stainless steel, the half-life a majority of the activation products is very short -- on the order of years, not millenia. If we use specially engineered materials (like vanadium alloys and SiC ceramics) we can get the activation to a minimum. The neutrons are NOT the radiation problem in a fission reactor -- it is the horribly radioactive fission products. These are unavoidable in fission and live forever. We could even ELIMINATE activation entirely in a fusion plant if we use advanced fuels like p-B11 or D-He3 (which are harder to get to fuse than D-T, but have NO neutron emission).

> The third myth is that fusion power would be cheap, not > so. Compared to a Fusion reactor a Fision reactor is just a pile of > metal, and we all know how cheap they are. Sorry guys, Fusion will > be the most expensive energy on the planet. > MYTH III: Fusion Power is Cheap, nope.

You are right here, the fusion plant is going to cost a lot, based on present designs. But it is not so far off as you think-- fission plants are quite expensive due to licensing problems. Fusion will only become economical when the price of other fuels rises (or if we start to internalize the costs associated with pollution -- and hence raise the cost of fossil power).

> So what does this tell us? We could get an even better > deal using fast and slow breeder reactors using fission > technology. It would provide all the energy we could > conceivably need, and using breeders with reprocessing > it would not only produce almost no new waste, but it > could burn as fuel about 99% of the waste we have > now. If done right it could be fairly cheap as well, and > extremely safe. So get an almost limitless supply of > cheap and safe energy and at the same time get rid of > 99% of our current nuclear waste, yup, fast breeders > sound good to me too.

I agree that fission reactors, with fuel recycling, are part of the energy answer (+ breeding -- without breeding the uranium supply would run out on a 200 yr timescale I think). My undergraduate education was in nuclear engineering (and physics), and although my Ph.D. work is in plasmas/fusion, I am still a proponent of using fission.

Actually, the airstrip is gone now... There's just a field there, where someone plants some crops. I haven't been at PPPL long enough to have seen the airstrip -- I was told this by a tech who has been (maybe you know him - Jim Taylor).

Getting the ions moving quickly isn't the only problem -- you also need to have a lot of them reacting and you need to have them interacting for a long time. The cross section for simple binary collisions between ions is much larger than the fusion cross section, and so the ions must undergo many scattering collisions before fusing -- so you have to keep them around for a while. (This is why we don't simply fire two beams of D and T at one another -- which is the easiest way to get a fast collision between two ions). The solution to this is to let the ions collide and become thermal, but keep them trapped long enough to fuse (hence the tokamak, RFP, FRC, spheromak, etc...).

Using electrostatic forces to try to trap ions in fusion is problematic because you need huge potentials to trap a reasonable number of ions (you have to overcome the potential the ions themselves create). You need something like 10^13/cc density to get a reasonable fusion power, and electrostatic traps can get up to (I think) 10^8/cc if they are really clever.

There is an experiment similar to the one you mention at U. Wisconsin (at least it was there when I was visiting grad schools a few years back). They are more interested in using it as a thruster for spacecraft, though (no fusion involved here). I couldn't find a link for it on www.wisc.edu [wisc.edu], though.

In fusion science circles "alternative" fusion research usually means studying thermonuclear devices that aren't tokamaks (for instance, NSTX, the spherical tokamak (they call it a torus now) here at PPPL). Other alternative research devices are Reverse Field Pinches (MST at Wisconsin), Stellerators (LHD in japan, there's also a big one in Germany and one under development here at Princeton), Field Reverse Configurations (U. Wash, my experiment here at PPPL can be run as an FRC)....

[Don't read this if you haven't seen The Matrix yet. I don't want to spoil it for you.]

If you believe what you saw in The Matrix, we humans are a great source of energy. We can't exactly go sticking everyone in energy-extraction pods permanently, though. (Well, maybe we already are in pods and/. is only a program to keep our minds occupied.) So instead we could just make sleep chambers that extract our energy at night. Hook your bed up to your electric car and voila, no more oil dependency. Turn homeless shelters into power plants. This is great!

Where are you going to get the antimatter from? Hard to find that stuff in my part of town. You could make antimatter if you had another energy source, but then you're really just making a battery. (Would be a great battery though; still very useful for spacecraft.) You have to remember that to make any fuel (electricity for your electric car, hydrogen for your fuel cell, or antimatter for your spaceship) you have to use energy from a primary source (solar, oil, deuterium).

As for zero state energy, I don't understand how you propose to perform useful work without an energy sink.

I think Philo Taylor Farnsworth, the inventor of the television set, was the original inventor of these electrostatic confinement devices. He had a working prototype in the 60s, though it produced far too little fusion at the time to attain "break-even." One modern experiment of the type that I know of is being built at Los Alamos. The primary difficulty with achieving fusion power out of these devices, if I'm not mistaken, is that the material in the center tends to become a plasma (exhibit collective behavior) if the densities become too high. Debye shielding then takes place and the efficiency of the fusion power production diminishes.

Even if this is true, the devices would still be quite useful as a neutron source (e.g. for detecting plastic explosives in airports or detecting the presence of fissionable materials). They have the advantage of being easy to turn off, unlike a chunk of radioactive material, and I think this is one of the short-term goals of the Los Alamos work.

Do any of you fellow nerds live within a 10 minute drive of Princeton Plasma Physics Lab? Not only can you go over and see it at lectures every now and then, but they give out free magnets and buttons with pretty pictures (and sometimes free food =)

Holders of world record in solar cell efficiency (~24%) They are working with Germany and Japan to provide rooftop systems to multi-thousand homes. Each rooftop installation provides up to 4KW peak power into the local electricity grid. Peak electricity needs are the most expensive to cater for when considering normal power stations. Example - California experiences peak power needs on hot sunny days when people most use aircon. Solar power generates most power on hot sunny days.

The money behinf the oil companies ( and the polotics) will influence the restriction of cold fusion due to the loss of business it would cause them if it ever gets "discovered"......cars that run on water? OPEC won't like that at all......

I agree with that, however, I'd bet that most houses average more than 4Kw, so even with perfect storage, we'll have problems. We also only get those 4Kw when the sun is shining, which is well less than 12 hrs per day, and only on sunny days. Lets say your in the Northeast US, where it's cloudy one day out of 4, and you average 12 hrs (for easy math) of sun a day. That would mean that you get: 365days*0.75*12hrs*4Kw or 13140Kwh per year of power from the cells (we'll assume 100% perfect storage) which leads to you having an AVERAGE of 1.5Kw available at all time. Anyone own a blow drier? That's it!

Off-grid solar houses of today use MUCH less power

Yep, they do, but most people aren't willing to live that lifestyle. They want their dishwashers, microwaves, large screen TVs, computers etc.

it's not unusual for a solar home to be able to power all typical shop tools, but maybe not all at once

I guess I have a Geek shop, my arc welder just won't cut it. Heck, I have enough problem ON grid (I also have a 12"lathe and 2 milling machines, plus woodworking stuff)

4KW, Wow, or about 115 volts, 35 Amps. Not much, we need other sources. The average house today uses 100amp service (220 volts), and most NEW houses need a 200 amp (220 volt) service. In other words, solar isn't practical to use ALONE until is can deliver at least 20Kw to the home during peak hours, and deliver say, half that, full time. Lets face it, or little PCs with the monitor use 200-300 watts

As a former high energy physicist, I'd like to comment that, as Fnkmster says, it is possible to produce anitmatter at particle accelerators. This is regularly done at accelerator sites around the world. Research is done with colliding beams of electrons/ant electrons or protons/antiprotons. As I remember, CERN has even produced some atome of anit-hydrogen ( http://www.cern.ch)

It takes a LOT of input electricity (read dedicated high voltage lines, the output of a pwer station, and no running during the winter when France needs the power!) to do this. So I agree that anti-matter won't be an economical fuel in the forseeable future. Then again as a weapon...

However, there is a great deal of interest in muon-catalysed fusion. This was first seen in bubble chamber experiments. Use a particle accelerator to create a muon beam. Target this on a tank of liquid hydrogen. The muons bind much more closely to the hydrogen nucleii and can catalyse fusion reactions between them, by allowing them to get much closer. If it pans out, a new way to get cheap fusion power for the world.

Comercial shipments of fuel cells have already begun. Most are to developing conutries that do not have much of a power grid. They are being used to supply power to remote villages and the such. They current generation are methane fueld I belive.

True, but the process of a microscopic black hole "disappearing" is really a function of it radiating all of its mass away as energy (via Hawking radiation at the event horizon). This is a tremendously energetic process, and would be observable, if it were happening in our vicinity in the solar system. It's not, and has never been observed, AFAIK. This implies that these random microscopic black holes are either much rarer than that, or just don't exist anywhere near enough for us to observe them radiating massive amounts of energy and exploding to nothingness, or the theory of Hawking radiation is somehow wrong. I don't know which of these possibilities is the most likely. But I do know that Hawking radiation makes sense, and I don't know where the theory that these microscopic black holes should be present everywhere comes from (I accept that there may have been many of them everywhere early in the universe, but those would have LONG ago dissipated).

Your explanation of Hawking radiation wasn't quite right, but I'm not gonna critique it since I don't remember enough of the details. But you don't get antimatter out, you get high energy radiation out (but only when the black hole radius is microscopic in dimension... for macroscopic black holes, Hawking radiation is neglible, and hence they are relatively stable).

Glashow is senile, I took a class from him (for a week) last semester before dropping it. He was brilliant, but he's past his prime.

Nevertheless, his conclusion is pretty commonsensical, and I'm sure it can be proved (as much as anything in astronomy/cosmology can be proved).

The point is, that antimatter can't really be found for free by any method I know of. It is moderately conceivable as a fuel for space travel, but would have to be produced, by using energy generated from other processes, i.e. fusion. Antimatter is just a more space efficient way to store this energy. We can't get the energy for free unless we have stuff sitting around with unusually high energy relative to what we convert it to.

Roads in the US probably do cover on order of 1000 mi^2. That's not really all that much road, if you think about it. Just thinking about the island of Manhattan, it's about 15 miles long, and has about 10 avenues, each of which is probably 50 feet wide (roughly, if you include sidewalks). So that's 1.5 mi^2 right there, on one very small, albeit densely populated island. And if you think about it, I-95 is about 2000 miles + long, and about 50 feet wide, so that's about 20 mi^2 right there, or 2% of your 1000 mi^2 figure. Anyway, I agree with you that the cost and feasibility of such massive scale solar power is not currently economically feasible. If/when energy becomes more expensive and more $$$s go into solar power development, it might become cheap enough for everyone to have solar panels on their roof,etc. Even if it couldn't supply ALL our power, it could put a big dent in power consumption.

Yes but you seem to miss the point. To operate these colliders, you have to put a lot of energy in. There is no known way to get antimatter for free. It is entropically unlikely that antimatter would form from matter (what you start out with before colliding), without putting more energy into the collision process than energy equivalent units of antimatter you obtain. You don't get energy for free this way. You just get a very compact, storable fuel that is 100% efficient in conversion to energy.

When researchers in a field make extravagant promises about breakthoughs that are about to happen "any day now" and decades go by without these breakthoughs actually coming to pass, scientific funding agencies are bound to come to the conclusion that the money would be better spent in more fruitful fields. Maybe now, with more background research, practical fusion energy really *is* just around the corner, but today's fusion researchers have to pay the price of the hype of their forerunners. Artificial intelligence is another field that is suffering from past overhype, and now in molecular biology, gene therapy may well be a future member of this club.

Though it may also be one of the riskiest gambles you take. However, I can't imagine a viable alternative off the top of my head...

Is there any corporation or research unit that wants funding? Perhaps a Slashdot collective, and if each user of all 200,000 of us sends 10 dollars, we could get some sort of share or ownership of the technologies involved =)

They really do need support in the US, however, for the critical nature of their research. More crucial and important the nuclear weapons or even social security...

Still waiting for the problems with the moderation system to fix themselves =)